Air filtering installations; Air purifying apparatus and machines; Air sterilisers; Filters for drinking water; Germicidal lamps for purifying air; Ionization apparatus for the treatment of liquids and gases for industrial, commercial or agricultural use; Pipes being parts of sanitary facilities; Regulating accessories for water supply, namely, metered valves; Swimming pool chlorinating apparatus; Water desalination plants; Water purification units; Water purifying apparatus and machines